From Russia with love

Nowadays the mass production allows us to buy a variety of analogue synthesizer for little money. These instruments are typically soldered by machines and mounted in plastic enclosures with (too often) a flimsy or toyish feel. In contrast the RITM-2 by the Russian Company VG-Line is high quality and hand build with a lots of love. It is basically a desktop recreation of the vintage version of same name, which was designed by Viktor Nikulin and produced Kirovsky musical instruments from 1984. The RITM-2 is a simple subtractive monophonic synthesizer with a single oscillator. I want to address the question why it might be worth to invest some extra coin for this sweet boutique synthesizer.

Clear and classic front panel layout

Specifications

The basic feature of the RITM are shared with the puristic original design:

• Single VCO core with Octave switch and PWM
• Mixer section for triangle/saw, square/PWM and noise generator
• 24dB low pass filter based on LM394 with tracking selector (1 or 1/2)
• LFO with triangle, square and stepped random
• Two ADSR for filter and VCA, the VCA ADSR is loopable
• Simple modulation selector for VCO and VCF

The VG-Line RITM-2 is a slightly expanded version of the original design:

• Build in Midi Interface
• Switchable Midi velocity, which affects the Sustain in the VCA
• Switchable synchronization of the LFO to Midi Clock
• External audio input, which is routed to the mixer section
• CV/Gate Interface with most popular 1V/Oct characteristic
• Additional CV Inputs for VCA, VCF, PWM

RITM-2 with a variety of CV options and DIN Midi socket

The changes are well thought and VG-Line totally preserves the look of the original instrument. Because the original design requires switch trigger and a very exotic -1.18 V/Oct scaling, the build in CV/Gate is a real bargain and game changer. The extended features are very comfortable to use and make the integration into modern studio environment easy and fast. The tracking and the tuning are also excellent.

Build quality

The synth is assembled in a sturdy metal enclosure, which is finished with a beautiful powder coating. The pots, sliders and switches feel very smooth and durable. The front panel keeps the character of the original layout. The desktop unit features some additional LEDs for power (color changes cyclic), Midi and ADSR. Especially, the ADSR LEDs give some valuable feedback of the envelope timing. There is also a TRS 3.5mm (1/8in) phones output with a separate volume control on the front panel, which is very handy for pre-listening in a live situation. Behind the side panels some trim-pots can be reached easily and also offers the view on the circuit board.

VG-Line selected high quality and special components like metal can transistors with Cyrillic printing on the body, reddish carbon film resistor, polyester capacitor (greenies) and sockets for the ICs.

The slits of the ADSR sliders are covered by a dust protection.

Sound capabilities

The oscillator shines with a very nice organic character with subtle instabilities, which also offers a lot of punch for low frequencies. The low pass filter oscillates at high resonance levels. The frequency range of the cutoff is huge and covers the full spectrum. The filter is very versatile and interacts in a very nice way with the oscillator. At moderate resonance the filter locks to overtones, which leads to a variety of subtle timbres. The noise generator has a more closed sound and differs (probably – I didn’t measure it) from a white noise spectrum. The noise level is also significantly lower than the oscillator level, which is an adaption from the original RITM-2. The overall sound quality is really superb and always very musically.

The routing possibilities are quite limited. The modulation sources are selected with rotary switches for the VCO and VCF each, i.e. each destination can be modulated by just a single source. The LFO speed ranges to lower audio frequencies, which makes some mild FM synthesis possible. The loopable ADSR of the VCA can be used for rhythmic syncopation or some dedicated AM with vocal sound. The switchable octave range underlines the performance abilities because there is no need to tune the VCO, if one wants to transpose the octave.

All in all, I really appreciate this puristic approach with some twists because tweaking a variety of sounds is very fast, productive and absolute fun. The synth is still much more versatile as one could expect from the puristic feature set and just in case: one is capable to extend the synthesis or modulations with the help of the PWM, VCF and VCA Input. The RITM-2 covers standard duties such as analog lead sounds, basslines or acid-like chirps (more fluid than rubber) with ease. Unfortunately, I am not able to make a direct comparison to a vintage RITM-2, but in my feelings VG-Lines put a lot of efforts to build a good recreation of the original sound. However, it brings an original aesthetics and shines with a dark and very lovely fragile quality, which reminds often of Soviet Sci-Fi movies.

Sound Examples

Either reverb (Catalinbread’s Talisman) or delay (Fairfield Circuitry’s Meet Maude) was applied. The recording is done in glorious mono. Some slight noises and overdrive could be a result of an incorrect leveling (I am sorry for that).

My conclusion

I didn’t expect it before, but I fell in love with this simple but amazing synthesizer (and this does not happen that often). It sounds a bit contradictory, the combination of sound and build quality as well as the puristic features are probably just the reason for that – for my taste even the LFO Sync option could had been dropped.
The overall character is very appealing and the given additional feature are chosen very well. Although VG-Lines released the RITM-2 already for a couple of years, public information about this project is still quite rare. The high price tag can be justified by the rock solid build and superb sound quality. One has to keep in mind that this a hand build niche product. In my opinion it deserves much more attention and love from the synthesizer community. At least my heart was won ❤ ❤ ❤

References

Many thanks to Max from VG-Line for some additional information!

Website of VG-Line RITM-2
http://www.ritm2.e-tera.ru/en/

Soviet synth database
http://www.ruskeys.net/eng/base/ritm2.php

CV/Gate Mod on the original RITM-2
http://www.modularsynth.ru/en/2013/06/17/ritm-2_cv_gate/

Frequensteiner-in-the-Box

Some basics

In my recent project I build a small dual filter box based on the well-known and loved Livewire Frequensteiner multimode filter, which has become a Eurorack classic over the last decades. The Frequensteiner module is based on the filter design by Steiner Parker Synthasystem from the 1970ties. It has a discrete core and is based on diodes. The filter slope is 12dB (low and high pass) and respectively 6dB (band pass).

The basic concept

I have to admit that after all the years this filter is still my all time favorite although the design is quite puristic (no V/Oct tracking, no CV of resonance, high noise floor). But the resonance sounds so very special – even with zero-resonance the filter colors the signal obviously. The filter FM is unstable and imperfect in a musical way.

The shallow 4ms 32HP Pod is used as the housing

The module has some known quirks: At high resonance turning the resonance knob will generate audible crackles, which is not caused by a mechanical issue of the potentiometer itself (some people may not like this behavior, but I like to use it as a crackle generator). The module is prone to catch audible noise and oscillations from the power bus. This can become annoying especially with digital modules and LEDs which often spoil the common ground of the modular system. I would recommend a separate power supply for the modules if you want to avoid significant signal bleeding.

Luckily, Steve R from Livewire still is still building the modules up to now, so I decided to build a very small filter box in a 4ms 32HP Pod, which is a perfect companion for very compact live sets. I decided to keep the concept as minimal as possible and omitted therefore any kind of additional modulators. The module layout is very clear. The space and the size of knobs makes it very playable, which is a very important factor for me. The box can be used for parallel (stereo) or serial (mono) filtering and doubles in function as a rather flexible sound generator. As a sound generator the spectrum reaches from pure sine to rich and wild cross-modulations.

Building a Freqbox

Ribbon cable with removed strain-relief at the header

The modules are build with through-hole parts which makes the modifications much more convenient. The suggested modifications make them playable without any additional patch-cords or multiples. If required, a normalization can be overruled by patching a patch-cord. In addition to the normalization the resonance behavior is fine tuned by changing two resistors. The filter becomes slightly more self-resonant, which is important to use it as a sine oscillator. However, the self-oscillation starts at approximately 12 o’clock (it does not cover low frequencies).

Normalizations (module A on the left, module B on the right hand):

• Input of module A to input of module B and vice versa
• Output of module A to CV2 input of module B and vice versa
• DC voltage to CV1 of module A
• CV1 of module A to CV2 to module B

Resonance modifications

• R12, 510 on PCB + 1k parallel = 340 Ohm in total
• R22, 10k on PCB + 10k parallel = 5k Ohm in total

Freqsounds

First example is pure Frequensteiner without changing any parameter during each recording interval. The sounds reflect the nonlinear and sometime chaotic behavior of the filter.

For the second run I added some FX and external input and modulation.
In the first examples I used the Electric Repeaters Horndog.  It is based on the Ciat-Lonbarde Rolzer circuit – basically interacting nonlinear oscillators. Next a drone machine Sleepdrone 5 by Skychord Electronics is tested. It is a 4 voice drone synth with CMOS based rectangular oscillators. Finally, a rather harsh noise box called Cacophonator II by Subtle Noise Maker is used as input. The Strymon Flint gives reverberation on all examples.

0:00 – 5:13     Electric Repeater Horndog
5:13 – 7:55     Skychord Electronics Sleepdrone 5
7:55 – 8:18     Subtle Noise Maker Cacophonator II

 

Are you experienced?

The legendary and ultra rare Buchla 100 system seems to be unreachable for a long time. During the last decade a vivid DIY scene started to clone the old modules, e.g. La 67 or Peake.

Nowadays, manufacturer like Catalyst Audio, Tokyo Tape Music Center or Low-Gain Electronics started to sell clones for Eurorack or in 4U format. Buchla announced recently (Sept 2019) an official re-release of the 100 series under the brand Red Panel, which are based on the Catalyst Audio Eurorack adaption, as well as official DIY kits of the original 4U version.

I decided to start my build of a small Buchla 100 clone in the beginning of 2018, where Catalyst Audio offered Eurorack compatible modules. Due to the lack of time (and probably skills) the DIY was not a realistic option for me. My main interest was driven by the inimitable sound of the oscillators and also by the (today’s limited) system design itself. In the following I want to share my first impressions and sounds of a my recently finished mini Buchla 100 clone.

Some initial thoughts

The modular should be based solely on the old module designs of the original Buchla 100 series with its limitations and idiosyncrasies in sound and operation. I prefer a compact system with a good focus on the characteristics, but it should be more complex than a simple monophonic voice. My collection should be limited on the core functions of a synth voice (VCO, VCA, MIXER, ENV), i.e. there will be no space for sequencer or more sophisticated control options, but it could be driven easily by external CV/gate.

Transistor driven circuit design

Another important aspect for my choice was a fully transistor based build with through-hole parts. In my opinion SMD production doesn’t feel right to me for a close re-creation of an ‘ancient’ modular synth. The 4U clones were excluded to keep it compatible to my given infrastructure and also to cut the expenses. The final build ended up as a small two voice system, which is composed of 8 modules.

 

Module selection:

• 2x Model 158, Voltage controlled oscillator (Tokyo Tape Music Center)
• 2x Model 156, Voltage processor (Catalyst Audio)
• 2x Model 180, Envelope generator (Catalyst Audio)
• 1x Model 110, Voltage controlled amplifier (Catalyst Audio)
• 1x Model 106, Audio mixer (Catalyst Audio)

Layout of the module selection

 

The modules by Catalyst Audio have a really great look and feel with powder coated panels. I also appreciate that the original Model 110 with a dual VCA was doubled to a quad VCA. Unfortunately, I missed the first batch of the Model 158, which were manufactured with through-hole parts. Thus, I switched to Tokyo Tape Music Center for the oscillators Model 158A and I am very happy with my decision. The build quality is very high and the circuit is based on NOS transistors, which sound very clean, but easily goes raw and wild if required.

Following functions are covered (in a beautiful symmetrical way):

• 4x VCOs
• 4x VCAs
• 4x Envelopes
• 4x Crossfader for mixing envelopes and provide offsets for VCO or VCA
• 2x Three channel mixer for stereophonic mixing (or six channel to mono)

Some specific characteristics

It is (probably) difficult to play the system tonally (I didn’t try it yet). In contrast to Red Panel the TTMC oscillators are calibrated to 1.2V/Oct, i.e. a pitch CV of a common 1V/Oct source requires an amplification and re-calibration. Furthermore, an external CV for the VCO requires an offset voltage. The offset and pitch CV is mixed with crossfading on the Model 156 (vintage version with transistors), which results in an attenuation of the pitch CV. This is the reason why Red Panel also offers a modern op-amp based Model 156M with a different routing.

But the vintage version of Model 156 includes a clever feature: the second unit offers an inverted CV input which is basically a DC offset minus the input CV. This allows a simple option for panning and voltage controlled crossfadings (remember that CV is always positive). Another nice trick is that the Model 180 envelope does not retrigger while running, i.e. it can be used two create n:m ratio of clock divisions from a single trigger source.

A beautiful wooden cabinet supports the vintage look&feel.

In the end, I was really surprised how easy and how nice one can patch quite sophisticated stereo effects with the combination of transistor inverter, dual audio outputs and the two mixer sections. Many analogue vintage synth do not support stereo outs or at least rather rudimentary stereo processing with for example a chorus. In the Buchla world stereo patching feels very natural and is quite comfortable. The modules are much deeper and sophisticated than they seem to be at first glance. And it doesn’t surprise that Don Buchla also experimented with quadraphonic effect boxes quite early…

Talking about signal levels

The modules by Catalyst Audio are buffered by an op-amp circuit and are capable to run on Buchla signal levels. The level type can be switched by simply changing a jumper on the back of the PCB. As far as I know, the main difference is the lower audio level on Buchla systems with +0db (approx 1Vpp) compared to +12dB in Eurorack (approx. 4Vpp). In the Buchla world audio and CV are separated by different jack types (tiny-jax for bipolar audio and banana jacks for unipolar CV). The eurofied modules only provide a single jack type (common mini-jacks), which makes it (at least level-wise) less useful to separate between audio and CV. There are still some caveats regarding AC/DC processing, e.g. the Model 110 VCA is AC coupled and does not support DC voltages at the audio input or the voltage processor Model 156 is restricted to positive voltages etc. At the end of the day, I decided to run the whole system in the Eurorack compatible mode because of the homogeneous jack types and the hot oscillator outputs.

Grandma’s synthesizer

Working with the system is more challenging and different compared to conventional Eurorack. There is no visual feedback by LEDs, missing offsets and parameters, which lack an automation via CV. It somehow feels like a historical instrument and I got an impression how laborious the early compositions from the 60ties were. The puristic features and the raw sound are though absolutely inspiring to me. All in all, it is rewarding and fun to work with, but I would not recommend it to a modular beginner.

The Buchla 100 test ride

I want to finish with some recordings of my first attempts. The demos were simply recorded without external CV/gate, i.e. a dual envelope was directly triggered by one of the four oscillators. The stereo out was processed by a Boss DC-2w, Strymon Flint and Redpanda Particle V2. Have fun!

Acknowledgments

First, I would like to thank Buchla for building such original instruments and bringing them back again. I am also very grateful to the community and all the people who were involved in the reviving the Buchla 100. My special thanks go to Dave from Catalyst Audio, Kurosaki from Tokyo Tape Music Center and Carl from Sawandsolder, who crafted this beautiful wooden cabinet.

When the far east meets the west coast

Here is a short review of the amazing Model 158 with NOS transistors crafted by Tokyo Tape Music Center Tokyo Tape Music Center (TTMC) from Japan. I do not want to keep back that Buchla recently announced the official recreation of the Buchla 100 Series under the brand Red Panel.

Tokyo Tape Music Center Model 158

As far as I know the new Red Panel designs are based on SMD production and a very careful replacement of old transistor types. However, if you are hunting a hand build through-hole design with NOS parts, which is compatible to Eurorack, TTMC might be an interesting option.

Some very brief history about the Model 158

The TTMC module is a Buchla inspired Eurorack clone of the Model 158, the first voltage controlled oscillator made by Don Buchla back in the 60ties. Due to its age it is a discrete design based on transistors. The original design from the Buchla 100 Series is legendary and celebrates it debut in the famous early electronic composition Silver Apples of the Moon by the well-known American composer Morton Subotnick from the San Francisco Tape Music Center.

The Model 158 layout

The layout of the Model 158 itself is quite puristic from a today’s perspective. It’s quite simple a dual oscillator with frequency potentiometer at the bottom.  The switch chooses between the internal frequency (set by the big knob) and the1.2V/Oct control voltage input.  The shape potentiometer crossfades between sine and saw (no CV option here). Finally, there is an AC coupled modulation input with an attenuator (i.e. DC voltages slew to zero).

Front and back showing NOS parts

The Tokyo Tape Music Center design

The reviewed version is the Model 158 V2 with NOS transistors (IT122, 2N4339, 2N5020) and upgrade of capacitors. Some details regarding the transistors can be found on
https://ebolatone.blogspot.com/2012/12/buchla-158a-pcb-build.html
TTMC also adds a second internal/external switch, which is very helpful to save resources in a small system because enabling the external control requires mixing and offsets of CV, which is typically realized with the Voltage Processor (Model 156). TTMC was very helpful and now offers white panels. The panels are made from PCB material. The dark panel has a rough surface and the white one has a very plain structure.

Dark and white panels

Some further technical specifications

The frequency response goes approximately from 5Hz to 10kHz. The tracking is the Buchla typically 1.2v/Oct in contrast to 1V/Oct tracking in the Euroland.  Actually I didn’t test the calibration. I do not care about tonal tracking that much. The 100 system is based on frequency modulation and in exponential FM the principal tune depends on the modulator. The output level depends on the shape and frequency (3.2v to 3.8v Vpp). In contrast to the original design, the TTMC output is compatible to Eurorack levels. It also pairs very well with the Catalyst Audio recreation of the 100 System (with activated op-amp buffering) and probably to the new re-branded Red Panel versions.

How does is sound?

In short: lovely and amazing! It easily does the full picture from pure and raw to very complex overtones. Chaotic patterns are also possible with a twist of a knob.

Sine wave of the NOS version

Saw wave of the NOS version

The sine is clean and pure compared to the conventional version without the NOS replacement. The example shows the frequency range, cross-fading between sine and saw, FM modulation with 50% and 100% depth and bunch frequency cross-modulation. The latter ones show the unstable nature of the discrete core. The evolving patterns were recorded without touching the knobs at all!

 

Acknowledgment

Many thanks again to Kurosaki, who is the awesome person behind Tokyo Tape Music Center!

a perfect rendezvous

analog dreams come true… this time we meet maude: an extravagant analog delay of the canadian company fairfield circuitry.

chaos computer hacking

this blog presents a simple add-on for the chaos computer by livewire. the modification is reversible and it is not necessary to disassemble the module.

the sidrazzi project

this blog documents one of my current diy projects, the build of an electroacoustic instrument called sidrazzi. in the first part the focus is kept on crafting the housing of this wonderful instrument.

rambling on meandering paths

this blog entry is a review of the new chaos computer module by livewire. the chaos computer is not only a modular eye candy, it is also an ear candy at its best…

i’d like to take two, please

after reviewing some high priced pedals, i’d like to discuss a pedal, which offers some interesting results at a rather low price tag: the auto-swell pedal by behringer. the SM200 is basically a budget clone of the sought-after boss SG2 slow gear. in this recent review, i’ll focus just on an application, for which the pedal was absolutely not intended: drum machines…

howling at the moon

the trinity of jupiter’s moon titan

the phase of the moon approaches jupiter’s elongation…

it’s blogging time again! this post will deal with a guitar pedal from the view of synthesists. my last blog treated the redpanda particle, which is a digital delay pedal specialized on granular synthesis. in comparison to the particle the pedal discussed next is similar but at the same time totally different. however, the still unknown candidate unifies simplicity, sonority and complexity in a small footstep and it’s a delay unit again…